The question is the following: which kind of labour "create" values? If we answer: it is productive labour "creates" value, then this answer is just a tautology. If we answer: it is labour that produces products and that is embodied in them "creates" value, then this answer is still ambiguous because you do not define what is the product. Can we say circulation workers produce "service products"? Are they labour embodied in such so-called "service products", and eventually, are their labour productive? The above answers are not satisfying, these answers still have something needed to be defined. So we need another criterion to judge what kind of labour "create" values. For Masako Watanabe (渡辺雅男. Sorry I just found him in Japanese Wiki, but you can translate this Japanese website page into English by Chrome), a Japanese Marxian economist, to evaluate whether the labour creates value, we need to check whether this kind of lab...
In Steedman's book "Marx after Sraffa", he proposed that in a joint production system, the labour values of commodities can be negative, which is in sharp contrast to Marxian theory of labour value. I am not meant to revisit his original argument and mathematical model here. If someone is interested in Steedman's argument, he/she can read the book "Marx after Sraffa". What I want to propose here, is a mixed version that makes me feel satisfied. This answer comes from Anwar Shaikh's "Real Competition Theory" and two Chinese modern classical economists: Feng Jinhua (冯金华) and Hou Hehong (侯和宏). Feng and Hou Let me introduce Feng and Hou's response to Steedman's critique at first. In 2011, they wrote a paper "Can Negative Surplus Value and Positive Profit Coexist?" (《负剩余价值和正利润可以同时存在吗？》), which was published in Journal of Renmin University of China (《中国人民大学学报》). In this paper, Feng and Hou point out that the labour term that appeare...